In transplanting larger plants, such as trees, it is important to excavate most of the roots along with the earth in which the roots reside. Plants that are transplanted with the least damage to their rootlets and root hairs have the best chance of surviving in a new location, all other things being equal. A plant is desirably moved along with a "root ball," that has most of its root still embedded in the earth in which the plant was growing. This allows the roots and the root ball to continue to nourish the plant after it is transplanted until new root growth can take place.
Any relative movement between the earth and the roots in the root ball, however, tends to break or damage the rootlets or tiny root hairs. Therefore, it is important for a transplanting apparatus to preserve a root ball and the supporting soil with a minimum of disturbance to the earth and root therein.
In particular, when transplanting trees, it is necessary to provide a container for the soil, which forms in combination with the roots of the plant, the root ball. It is during the digging and planting phase of the process that care must be taken to prevent damage to the root ball which might kill or stunt the growth of the plant. Separating the plant from the stock container or during the above-mentioned transfer operations is generally when damage to the root ball occurs, and it is these reoccurring problems to which the present invention is directed.
A common method of transplanting trees is to use a wire basket and burlap bag, which is wrapped around the root ball and secured with twine to the trunk of the tree. This traditional system is actually most unsuitable because the root ball may be easily damaged through normal handling and transportation, often in the back of a flatbed or pickup truck, wherein normal road vibration causes much of the soil to separate from the roots themselves. In any event, during the transplanting operation, the wire basket and burlap bag provide limited structural integrity to the root ball.
Thus, the ideal solution is to provide a transplanting pot or root ball containment vessel which would conveniently receive the root ball and be safely and easily removed from the root ball. Nursery stock containers which may be disassembled at the transplanting site are well known in the art. However, many such containers have either not adequately simplified the root balling procedure or eliminated the chances that damage will occur to the root ball while receiving the root ball or during the disassembly process or the transfer process.
Lightweight containers made from materials such as pressed fiberboard or paper are generally not reusable. Such containers are also not sufficiently durable to withstand the rigors of the nursery setting where stock is transferred about and finally shipped to the transplanting destination. This is particularly true with heavier plants which may weigh 250 pounds. Additionally, the root ball may be of a size which requires a container with a capacity in excess of three gallons. Further, if such a container is left to surround the root ball after transplanting in the ground, the growth of the plant is necessarily retarded until the fibers of the container material deteriorate to the degree necessary to allow the roots to be freed from the ball and extend into the surrounding soil.
Finally, manufacturers of containers constructed of flexible materials, such as plastic, have struggled with the problem of creating a lightweight, resilient container, which also has the structural integrity and simplicity to be used in the field both during the root balling process, handling of the container and the transplanting of the tree. In order to accommodate the structural requirements of the tree containment vessel, prior art devices have required the excavation of an abnormally large crater in the ground, and have required an unusual amount of dexterity and/or the presence of hand tools in order to disassemble the container once the tree is placed in its final transplanted location.